One annoyance of the Apple TV has always been the inability to move the icons around to fit your use habits. Whatever order Apple placed the icons in is what you were stuck using. As of Apple TV OS version 5.1, users can now rearrange the icons into an order better suited for them.

Well, there's one exception. You can't move any of the icons on the top row, only the bottom three rows. For whatever reason, Apple would rather you not hide the Movies or TV Shows icons (among others) down in the bottom row.